Vent valve



June 28, 1960 R H, HAHN ETAL VENT VALVE Filed Sept. 18, 1957 r, www i VM@ nited States Patent() i' search & Development Corp., 7530 San Fernando Road, Sun Valley, Calif.)

Filed sept. 1s, 1951, ser. No. 84,663

1o claims. (ci. 1an- 6255) This invention has to do with -a valve and is more particularly concerned with a manually operable vent valve for releasing pressure in ya system handling liquid oxygen, or the like.

In systems adapted to handle liquid oxygen, as for instance systems installed in high altitude aircraft for supplying oxygen to the pilot and including a suitable pressure supply tank, it frequently becomes necessary to vent the system and release lthe pressure therein as for the purpose of refilling the supply tank.

The valves ordinarily used to vent such systems are conventional poppet-type valves having rotatable screwtype operating stems projecting therefrom `and provided with suitable hand wheels, or the like, at the outer ends thereof. Due to the extreme low temperatures and high pressures encountered while venting such systems, which temperatures and pressures approach minus 300 F. and 300 p.s.i., it is impossible to properly or adequately seal around the rotating operating stems of the ordinary vent valves, with the result that as the valves are opened, liquid oxygen leaks out about the stems. Such leakage lowers the temperature of the hand wheel to a point where it is much too coldV to touch or operate by hand. Further, such leakage often occurs so rapidly and at such a rate that the hand of the person opening theVV valve is severely frostbitten or burned. Still further, the ordinary or conventional vent valve usedin such systems have metal seats and metal valve elements which are xed rigidly to the valve stems and are engageable against the seats. When the valves are opened the engaging surfaces of the seats and Valve elements frequently become frosted, and to a degree as to prevent proper seating of the valve element when it is desired to close the valve. When this occurs, the valve remains cracked and allows liquid oxygen to escape from the system. Still further, due to the extreme changes in temperature and as a result of expansion and contraction of various parts of the ordinary vent valve construction, when it is opened and closed again, the valving surfaces. frequently cannot be brought into proper seating engagement with each other in one operation, but must be adjusted several times yas the temperature of the construction returns to normal.

An object of the present invention is to provide a vent valve construction for use in systems handling uids suc-h as liquid oxygen at extremely low temperatures and at high pressures, which valve has a novel leak-proof operating mechanism and is such that it can be operated without leakage labout the operating stem vand the resulting hazards normally associated with such Valves.

Another object of the present invention is to provide a valve of the character referred to having a novel valve seat and valve element which is not adversely aiected by the extreme Variations in temperature and resulting expansion yand contraction of the elements of the valve construction.

A feature of the present invention is to provide a poppet-type vent valve having a longitudinally shiftable 2,942,622 Patented June 28, 19,60

valve stem projecting into a trap chamber remote lfrom the tiow passage in the valve, a manuallyl operable .longitudinally shiftable operating stem projecting into the trap chamber to engage the Valve stem Iand a longitudinally extendable bellows Vseal within the said trap chamber and extending between the stems.

Another feature of our invention is to provide a valve seat having a sealing ring of yieldable material such as polytetraliuoroethylene, engaged therein, which ring -is engagedto a predetermined extent by the valve element when the said elementqis fully engaged in the seat and so that 4the ring is not subject to being mutilated and rendered ineffective as by extrusion, or the like, when the valve is closed.

An object of the present invention is to provide a novel vent valve of the general character referred to which is easy and economical of manufacture andwhich is both highly effective and dependable in operation.

The various objects and features of our invention will be fully understood Vfrom the following detailed description of a typical preferred form and application of our invention, throughout which description 1reference is made to the Vaccompanying drawings, in which:

Fig. l is -a perspective View of the valve construction that we provide and showing it engaged in a well provided in the skin or surface of yan aircraft, or the like, and related to a lter cap located within the well.

Fig. 2 is an enlarged detailed sectional view of our valve construction and showing it in an unactuated or closed position.

Fig. 3 is -a view similar to Fig. 2 and showing our Valve construction in an actuated or open position.

Fig. 4 is an enlarged detailed sectional view of a portion of the Yconstruction that we provide and showing the seat yand Valve element in closed relationship with each other.

Fig. 5 is a view similar to Fig. 4 and showing the valve seat and valve element in an open position.

The valve construction A provided by the present invention is particularly adapted for use in connection with an oxygen supply system B in an aircraft, which system is shown as including, a pressure supply tank 1l), -a iiller pipe 11 projecting upwardly lfrom the tank, an outlet pipe 12 communicating with the tank, and a delivery line 13 communicating with the outlet pipe and adapted to conduct oxygen from the tank to the cabin or cockpit of the aircraft and other apparatus normall associated with such systems. e

The filler pipe 11, in accordance with normal aircraft construction, is shown projecting upwardly through the bottom wall 14 of a well 15 provided in the skin 16 of the aircraft to which it is related, to terminate below the plane of the skin, and is provided with a suitable closure cap 17, which is screw threaded onto the upper end thereof. The well 15 into which the filler pipe projects opens upwardly and is provided with a suitable hinged cover plate 18, which plate, when closed, is ush with the skin 16 of the aircraft.

The valve construction A is shown as including a body C having a flow chamber 20 and a trap chamber 21, an inlet port 22 connected with the outlet pipe 12 to establish open communication between said pipe 12 and the ow chamber, an outlet port 23 to connect with the delivery line 13 of theV system B and establishing open communication with said line and the ow chamber, a vent port 24 communicating with the flow chamber, and a Valving means V arranged within the flow chamber and adapted to selectively control the oW of uid in the ow chamber out through the outlet and vent ports. The construction is shown as further including manually operable actuating means D related to the valve means V and projecting through the trap chamber 21 of the body 'asalta-622'` y t Yi() 'fthe' exteriorof VVthe construction, and sealing means S'- within the trap` chamber'and establishing a liiuidl tight -seal YVbetween Vthe body and actuating mean's Ihe body C oLthevalve construction A `that we provide isa elongate-vertically[disposed-member formed' as by The/:dow and trap chambers .21' ettdzlong" tlx'dnallyofl the bodyi and: are located in'theupp/er'and' i lower'portions of'the'body; Y `Theichan'ibers.2!) and 21 -a'r t Yseparated one from the otherj Ywby'aj central horizontally f disposed' partition y25.1 t

' Y TheV lower end of*` thelowVchamberZd is closedbyftV plug-like insert 26 threadedlyengagedrin thelowert 'rami Vein argine may,l wane the npperrgendfffzae. Vtrap chamber is closedV by'ajplatelike'cap 27,"whx'ch cap isfsecuredto'theV bodybyra plurality ofrcircumferentmlly spaced screw fasteners'ZB; as clearlyillustrated throughout the drawings.

The lowerllow chamber ZGeXtendslongitudinally of t the lower portion of the .body Yand has a lower portionY 39 extending upwardly from they lower terminal end ofV the Y VVof the body/,C and establishes open communication'with the lower portion 3i) ofthe ow chamber 20, below Vthe l shoulder A suitable laterally outwardly projecting fboss 33 is provided on therbody in axial'alignment with the inlet'port 22. The bosst33 is internally threaded asV at 34 and threadedly receivesVV the end of theA outlet pipef 12 extending from the tank 10 and which is adapted to conduct Vtluidgfrom the tank through the port and into the saidiiow chamber'.

The outlet port 23'is .a central verticallyY disposedcand Y downwardly opening port extending longitudinally through festablishbearing engagement against the vdonfnwardly facing shoulder 31 therein and-having' a radially inwardly and upwardlytinclined'annular seating'face 51, an elongate vertically disposed valveelement'SZ having upper and lower radially inwardly/inclined sealing facesV 53 and 54, and engaged in the ilowf passage to be selectively shifted into and `out of engagement withthe seating face 51 of the lseat ring and the Vvalvekrseata in the plug-like insert 26 engaged Yin the `Vloyver end of the lflow passage and to thereby selectivelyr controlY new of Vfluid;through the outlet'and vientfports 22 and 24. The valve means V isl shownas further includinga compressiony spring 55 between thevalve element 52 and the topd'of'the insert 26 and adapted/to normallyyieldingly urge theisaid valve element upwardlytinto engagement with the seat ring 59, and aV longitudinally shiftable valve stem 56 engaged with the valve element, 52 tro project upwardly therefrom,

through the partition 25 in the body C andinto the trap chamber 21 where it' is engaged by the manually operaableactuating means D, and the sealingmeans S, as vwill Vhert'einafterY be described.

Y AIn the case illustrated, the valve element 52 is pro'- videdV witha downwardly facing annular shoulder 57 and against which the upper end of threjspring 5S engages or seats'. In the YVpreferred embodiment of the invention and as clearly illustrated in Figs. 4 andS of the/drawings, the sealing face 51V of the seat ringg is provided with a downwardly opening annular' groove 5S and in` which Vdling'oi'liquid oxygen, without becoming brittle or otherwise'breaking down'and/orbeing rendered ineffective.

the insert 26 engaged in the lower end portion'of the o'w passage'li. VThe insert 26 has a flat horizontally disposed top 35, which occurs in spaced relationship from and opposes. thefshoulder 27 inthe body and provided with an upwardly disposed annular inclinedfvalve seat '35,' concentric witlrtli'e port 23 extending'Itherethrough.

The' seat $6/ has an zannular groove 35' about'itsV outer;

" erihe'r Vand in which a suitable sealinf'ring 37 isen i f Y Y Y o.

lgaged. The sealingring'V 37 tprojectsupwardly from the seat.' .The Vseat rand'the sealingringjare adapted'to Jcooperatewith an element ofthe Vvalving[means V.as

will herein'after'be described.V Y Y Y ,The 'lower end off' the insertl 26Y is provided 4with an internally threaded. tubular extension V37 adapted toV threadedly Yreceive the end of the delivery'line i3 or". the

' system B, as clearly illustrated throughout the'drawings. Y

The sealing ring 59`-projects axially from the seating face 51; Y Y y f The angle or inclination of the seating face 51 on the seat ring 50 is more lacute than the angle or'i'nclination Vof the sealing face 53 on the valve elementSZ, with the result that when the Vvalve element is shifted upwardly and into VengagementV with the seat1ring'f50,zthe sealing face-53l thereof only engages the-inner Yperiphery of the `Yseatface 51 and the said seat'face/ and sealing facey diverge'as lheyrextend radially outwardly,V as clearly illustrated'in FiglA of theadrawings. i l

Y ithfthe aboverelationship offparts, irt'fwill be ap- Y parent'that when the valve element is seated in the' seat ring, thesealingface 53 thereof engages andseals` with Y the sealing` ring 59, but is stopped from establishing excessive pressure engagement therewith, or engagement Ywhich would result'in extrusionV and mutilation of the sealing ring.

The sealing'ring 37 and seat S6 of the'insert 261mlated tothe outlet port 23 cooperate with the Vbottom vided on the body C in yaxialalignment with thervent yport 24, which boss is internally threaded as at 39' and threadedly receives a suitable vent pire 4l?, which pipe extends to a suitable exhaust point or station spaced from the construction. j

' The upper trap chamber 21 has'a substantially straight 'bore continuing upwardly from the partition 25 to a point VVadjacent the upper terminal end of the-body. The upper terminal end of the body isl provided 'with a radially inwardly andnpwardly opening annular recess il about Y the bore of the' chamber and adapted'to cooperatively receivean element of the sealing, means S and a down- 1 wardly projecting annular VribV 42 provided'onV the under or bottorn'side 'of the cap 27, as clearly illustrated in the drawings andVY as will hereinafter *beV described-` t The valve means V that We provide is Vshownas includt Y ing an annular seat ring 50 pressed or otherwise engaged finto the lower portionl 3d of the dn/'chamber Z0 to face 54V of the valve Velement 52 in the same manner set forth above. l

With the construction that we provide, it `vvill be apparent that the valve element 52 establishes limited Vand controlled bearing( and sealing engagement on the sealing rings 37' and 59. Y

The valve stem 56 of the means V is an elongate'verti'- cally disposed member slidably engaged in an upwardly opening socket 60 entering the upper end of the valve element 52, to project upwardly therefrom and through he partition Z5 in Vthe' body and into the trap chamer21. Y

The partition 25 is lprovided with a suitable central Vlongitudinally.' disposed'KV boss 61 projecting'upwardly'into the trap chamberand having a centrally'longitudinallyV mallys'paced from the'bottomfof the socket. Y60 in the valve element 52 and isV provided with al downwardly Vopening recess-'V63Y opposing the bottom or thevsoeket. A

il 'W apanage' compression spring 64 is engaged in the recess 63 to project from the lower terminal end thereof and engage the bottom of the socket 60 and normally yieldingly urges the valve element downwardly relative to the stem.

The upper terminal end of the valve stem 56 terminates at a point intermediate the upper and lower ends of the trap chamber 21 and is provided with an upwardly pro-y jecting extension 65 of reduced diameter, which extension is adapted to connect with the means D asV will hereinafter be described.

The manually operable actuating means D is shown as including, a central elongate vertically disposed tubular post 70 projecting upwardly from the cap 27 secured to and closing the upper end of the body C, an elongate vertically disposed actuating stem 71 slidably engaged through the post to project into the trap chamber 21 and connect with the upper terminal end of the valve stem 56, a compression spring 72 normally yieldingly urging the actuating stem upwardly in the post and a cam actuator 73 pivotally carried by the upper terminal end of the post and engageable with the upper terminal end of the actuating stem and operable to shift the operating stern 71, valve stem 55 and valve element 52 downwardly in the construction.

The lower terminal end of the operating stem 71 is provided with a downwardly opening recess 74 in which the reduced extension 65 on the valve stem is engaged and bottoms.

The upper end portion of the post 70 is notched or slotted to establish a yoke having a pair of laterally spaced upwardly projecting legs 75 between which the cam actuator 73 is engaged and pivotally supported.

The cam actuator 73 is shown `as including a at vertically disposed plate-like body 76 arranged between the legs 75 of the yoke at the upper end of the post 70 and 1s adapted to engage the upper terminalend of the actuating stem. The body 76 is shown provided with an elongate operating arm 78 projecting laterally therefrom, which arm is engageable to shift or rotate the body relative to the yoke and the actuating stem. The body 76 is carried and supported between the legs 75 of the gate by a suitable pivot pin 79, which pin intersects the central vertical aXis of the body. The pin 79 is suitably secured to the legs to extend therebetween and through the cam body, as clearly illustrated in the drawings.

The compression spring 72 of the actuating means .D is adapted to normally yieldingly urge the actuating stem 71 upwardly into bearing engagement against the actuator 7 6. In the case illustrated, the spring 72 is a simple helical compression spring engaged about the upwardly projecting boss 6l on the partition 2S and the valve stem 56, to occur between and bear against the partition and a flange or disc fixed to and projecting outwardly from the lower end portion of the actuating stern 71. The disc referred to above, is part of the sealing means D and will be described as follows.

The plate-like body 76 of the cam actuator 73 has a substantially downwardly facing bottom edge 81, which edge engages the upper end of the actuating stern 71. The edge 81 has end portions d2 and 83 and a substantially square, downwardly projecting lug-like central portion 84 which is offset from the pivotal axis of the plate and normally occurs at one side of the actuating stem, as clearly illustrated in Fig. 2 of the drawings. When the cam is in the unactuated position illustrated in Fig. 2 of the drawings, the actuating stem is allowed to be shifted upwardly in the body C by the spring 72 and the valve element 52 and valve stem 55 are shifted upwardly in the body by the spring 55, so that the said valve element engages in the scat ring 50, thereby preventing the dow of iiuid or lo of pressure from the lower portion of the flow charnber 29 into the upper portion thereof and out through the vent port 24. When the cam actuator is rotated in the direction indicated by the arrow X in Fig. 3 of the drawings, the central portion S4 of the actuating stem 71 urgesV the valve stem 56 and valve element 52 downwardly in the valve body C, against the resistance of the spring 72 and 55 yand so that the valve element is shifted from engagement with the seat ring 50 and into engagement with the seating face 36 on the insert 26 in the lower end of the flow passage, and into sealing engagement with the sealing ring 37 carried thereby, thereby shutting olf ow through the outlet port 23 and allowing for the free ow of tluid and the release of pressure within the ow chamber 20 and the pressure tank 10 connected therewith, out through the vent port 24. When the cam actuator is fully 4shifted in the manner set forth above, the lug-like central portion 84 of the bottom edge of the plate-like body occurs in the other or opposite side of the actuating stem 71.

The said lug-like portion 84 on the bottom edge 86 of the cam is adapted to go over the center when it is fully shifted to either open or close the valve and so that it will not accidently work, or otherwise open and close the valve once it is actuated or shifted to either of the above-mentioned positions.

As a result of the above, when the valve is shifted to the open ,position where the valve element engages and seats on the seating face 36 on the insert 26 in the lower end of the body, the valve stem 56 must travel downwardly and then upwardly a short distance in the socket 60 in the valve element, against the resistance of the spring 64, after the valve element is seated and as the said central portion 84 of the cam element shifts over center.

It will be apparent that without the particular lost motion connection (60, 63 and 64), between the Valve stem and valve element, or some other lost motion or resilient coupling in the drive between the cam actuator and the valve element, the cam could not be shifted over center without jamming the construction or damaging the valve element.

In the preferred carrying out of the invention, a suitable cam follower is provided at the upper end of the actuating stem 71. In the case illustrated, the follower is a simple, ball-bearing S5 engaged in a spherically curved pocket formed in the upper terminal end of the actuating stem.

The operating arm 78 of the means D normally .projects substantially horizontally from the body 76. In the preferred form of the invention, the valve construction is related to the filler pipe 11 of the oxygen handling system B, so that the outer end portion 7 8 of the operating arrn 8 overlies the closure cap 17 on the fil-ler pipe, as clearly illustrated in Figs. l and 2 of the drawings. With this relationship of parts, it will be conveniently apparent that the operating arm 78 serves as a safety device, since the closure cap 17 cannot be unscrewed and removed from the filler pipe 11 until the ann is actuated or shifted upwardly and out of position over the cap. As pointed out above, when the arm 78 is shifted upwardly the pressure within the tank 10 is released, thereby making safe removal of the cap from the filler pipe possible.

When the valve is actuated, the operating arm 78 of the means D projects substantially vertically from the construction and out of the well 15 in which the construction is engaged, as clearly illustrated in Fig. 3 of the drawings. With this relationship of parts, the operating arm 78 serves a second function as a safety device, since it prevents the closure plate 1S for the well, from being closed, when the valve is opened.

In the form of the invention illustrated and to assure proper positioning of the actuating arm and to prevent the occur around the lower portion of the actuating stem,

ai.top,.-radiall y projecting Amounting -ange 92. fixed tothe upper endy ofthe bellowsV 90.,.and seated-.inthe Vannular reeeSsAi. ara'diallyliiiwardly .projectingbottom flange 9&at thelowfv ergend'go-fjbthzebellows `and tixedto the lowerend portion,

ofltherggactuating. stem ,7L

The top ilange-9'21at theupperend ofthe. bellows 90 Visgheld 'inclamped' sealed engagement Vin .therecess 91 bygthe annular Y rib 142. provided 'ongthe underside of the Y cap 27. t In practice, a suitable sealinggring -94 .is` inter-` posed between the said ilangler92 andthe rib 42 to assure a iiuid tight seal betweenV theflanggcap and body.

The bottom ange93atthef1owerend of the bellows.. is. secured to thelower endpiortiorrof .the actuatingstem f 71 in such a manner as to prevent `the passage of huid, therebetween and-serves las v:arseatrmember forthe compression springjf72. previously, discussed,

With the aboverelationshipof parts, v1t fwill be; apparent f that thejbellowstl of the ysealingmean-svS-Y posltively pre-lV ventsfftnerpassage offiluid l.from the.. lower portion of the.

Y trap chamber'Zl into the upper portionrthereof where.

itlwould'or. could ow outwardlydaround the ,actuating stem; or.-. out between the-body C andthe cap 27, but 1s 'such that it allows vforlfree,longitudinal shifting fof Jthe actuating;andwalvefstems3 71 and 56 ertendinginto the..

Said '.Chamber.-

In practice,v the bellowsris V,formed'of bronze, or some other-psuitablematerial whichfisofsuicient strengthto 1 stand up under the pressures encountered .inthe handling.;

of4 liquid oxygen., and is ysulrthat ritis not adyersely vaffect- Y Ved'by thefextremes in temperatureencountered-in;thef

handlingrof liquid-oxygen.

In light-.of the. foregoing,1 itV willi be .apparenti that we*V provide a.: novel vvalve construction particularly adapted .for ventinglsystems handlingliquidoxygen, or the like,;

and a construction which is simple, practical andhighly effective and dependable. in operation.

Having .described Vonly. a typicalopreferredvform and:

application of `our invention, we donot wish tobe limited or restricted Yto. the speciiicdetails aherein set-forth, but.

Vwishl'to` reserve=to lourselves-:anyvariations or fmodiiications that may appear to those skilled in the art and fall Vwithin thescope of the following'lclaims.

Having described our invention,v we claim:

l. A vent valve of the' character referred to including, an elongate vertically disposed body having an upper trap chamb'er'and an elongate lower Yilow chamber, an -inlet port in the body and lcor'mminicating with vthe ow chamber intermediate its vends, anroutlet portV in the body and .communicating with the flow-chamber at its lower'end, a

vent .port in the body land communicating Vwith the ow chamber at its upper end,`valving meansY within the ow ldepend-ing into the trap chamber to engage the.4 yalve st e1n,. a lever Yoperated overt-centercam, rotatably carried rorided in .theupper end of. the .body C, .and

;'. ing, .all elongatefyertically disposed `body-having.arrupper 'and V'eht ports communicating therewith s and having? a longitudinally shift'able valve f 'stemt fV-projecting.; upwardlyV .fy and into thie;trap,chamberto terminate*therein,F actuating means carriedbythebod-y atri-the upper-.endthereof .and including@ VAvertically` shiftable actuating stemA .depending intoi the trap chamber l to.' engage the .fvalve` stem,. a lever;V

operated overthe: centerI cam frotatably carried. byjfthee tbody and engaging the upper end of the actuating stem and ,sealing means `.between Vthe actuating stem.- andthe body, V,saidvalving means includinggan` annular. seat ring xed in-,the "iloW-= chamber'-L between :the inletband venta ports, `avvalve element :in the 4vilow-- chamber below the` 'seat ring and yieldingly coupled with the :lower vvendiof z thevalve stem, andf a compressionspringim the ow' chamberbelow the valvememberfand yieldingly urging. the; -said memberupwardly into: engagement with the a.

seatring Y 3. Af vent V,valvefot;- the-:charactenreferredto: includ trap chamber; andan; elongate; lower .oW-A chamber, an inlet port in ;the. body .'andzcommunicating with :the .ow

f chamber intermediate its ends, an outletport `:infthe body.:

*and .communicating `with..th'efilow chamber at its lower end, a Ventport in the -bodyzand Yizomrnurnicatingwith the .Vow chamberat itsi'upperend,:valving'means within the ow chamberV to control the ow of fluid through theoutlet iand :vent ports;` .communicating therewith .and- Vincluding .verticallyjspacedfvalve 'seats'.inthef-ilowfpassagefv .to occurabove .and belowthe inlet port, a-valve .member shiftablefbetween 's aid seats Aand a longitudinally shiftable fvalve stemprojecting-.upwardly and into the-trap'chamber tov'terminate'thereinand yieldingly coupled with the valve-- anda-member, actuating-means carriedv by. the -body vat the upperfend thereof andAA including arvertically shiftable actuating stem Vdepending intothe trap'chamberto engagethe valve.stem,'a levenoperated over-center cam rotatably carried by' the -bodyf and 'engaging lth'enpperY end V"of, the" actuating'stem, andseal-ingfmeans between the actuatingV stem andfthegbody, said--sealing-means includinga bellows sleeve: engaged "in 'the` trap. chamber and lhaving a e ange. at its :upper end secured to and-'sealedY with-the body-and a flange at-itslowerr end secured to and sealed? with the actuating stem.=

4. -A vent valveof the character Yreferredft'oV including,

Y an .elongatevertically disposed body'ghaving ianupper 5 upwardly and into the trapz chamber to terminatetherein, atuatingmeans carried. by the, body. anthe upperend.. Y thereof andfincludinga vertically shiftable actuatingstem by` thebody andrengaging theupper end of rtheactuating stem, andbellows-type sealing means betweenAthewactuating stem and the body. 2. A vent valveof the character referred to including an elongate vertically disposed body having Vlan upper trap chamber and an elongate lower flowchamber, aninlet port-inthe body and fcommunicatingwith the flowchamtrap chamber-fandY anl elongate lower viow "chamber, Van inlet port in the body and 'Y-communicatingwith'the ow'chamber intermediate v-its`ends, anoutlet Vport in the body andcommunicatingwiththe flow chamber at its lower fend, a vent port in vthe'body'and communicating, with thelowchamber--at'its upper end,Z valving means Within'the ow chamber to control Athe flow of uidy through thefoutletl andfv'ent ports1comrnunicating therewith and having a longitudinally shiftable Vvalve stem projecting upwardly and Yinto the trapchamber to terminate therein,actuating means carried by the body at the upper end thereof and including a vertically shiftablev actuating stem depending into the trap chamber to engage the -valve stem, an over center disc cam with an operating arm projecting therefromY krotatably carried by'the body' and engaged with the upper end ofthe actuating stem; and sealing means between the actuating'stem and the body, said valving means including an annular seat ring fixed-in the ow chamber between'the inlet and vent` ports, a `valve element in the flow chamber below theseat ring and yieldingly coupled with the lowerV end of the valve stem, and a compression :spring in the How-chamber` said sealing .meansincluding Va bellows. sleeve engaged. in"

' thetrap .chamber and havingv a flange at. its vupperenclV secured to f and v,sealed f with .the jbodyf and a zange .atQits i lower-end secured-to andsealed with'the. actuating stem..A

ung. 2

aplasta 5. A vent valve of the character referred to including, an elongate vertically disposed body having an upper trap chamber and an elongate lower iiow chamber, an inlet port in the body and communicating with the flow chamber intermediate its ends, an outlet port in the body and communicating with the How chamber at its lower end, a vent port in the body and communicating with the iow chamber at its upper end, valving means within the flow chamber to control the ilow of iiuid through the outlet and vent ports communicating therewith and including vertically spaced valve seats in the dow passage to occur above and below the inlet port, a valve member shiftable between said seats and a longitudinally shiftable valve stem projecting upwardly and into the trap chamber to terminate therein, and yieldingly coupled with the valve and member, actuating means carried by the body at the upper end thereof and including a vertically shiftable actuating stem depending into the trap chamber to engage the valve stem, a lever operated over-center cam rotatably carried by the body and engaging the upper end of the actuating stem, and sealing means between the actuating stem andthe body, said actuating means including a cap secured to and closing the upper end of the body and having an upwardly projecting tubular post slidably receiving the actuating stem, a cam plate having an overcenter log rotatably carried by the post and urging the upper end of the actuating stem and having a laterally projecting actuator arm projecting therefrom, and a spring in the trap chamber and engaging the actuating stem to force it upwardly into engagement with the cam plate.

6. A vent valve of the character referred to including, an elongate vertically disposed body having an upper trap chamber and an elongate lower ilow chamber, an inlet port in the body and communicating with the flow chamber intermediate its ends, an outlet port in the body and communicatingr with the flow chamber at its lower end, a vent port in the body and communicating with the iiow chamber at its upper end, valving means within the flow chamber to control the 'iiow of iiuid through the outlet and vent ports communicating therewith including vertically spaced, annular valve seats in the flow passage to occur above and below the inlet port, a valve element in the flow passage between the seats, means normally yieldingly urging the valve element into engagement with the upper seat and a longitudinally shiftable Valve stem yieldingly coupled with the valve member and projecting upwardly and into the trap chamber to terminate therein, cam operated actuating means carried by the body at the upper end thereof and including a vertically shiftable actuating stem depending into the trap chamber to engage the valve stem, and sealing means between the actuating stem and the body, said actuating means including a cap secured to and closing the upper end of the body and having an upwardly projecting tubular post slidably receiving the actuating stem, an over center cam plate rotatably carried by the post and engaging the upper end of the actuating stem and having a laterally projecting actuator arm projecting therefrom, and a spring in the trap chamber and urging the actuating stem upwardly and into engagement with the cam plate, said valving means including an annular seat ring iiXed in the flow chamber between the inlet and vent ports, a valve element with a central socket in the ilow chamber below the seat ring and slidably receiving the lower end of the valve stem, a compression spring in the socket to urge the valve element downwardly relative to the valve stem and a compression spring in the flow chamber below the valve member and yieldingly urging the said member upwardly into engagement with the seat ring.

7. A vent valve of the character referred to including, an elongate vertically disposed body having an upper trap chamber and an elongate lower iiow chamber, an inlet port in the body and communicating with the iiow chamber intermediate its ends, an outlet port in the body and communicating with the liow chamber at its lower end, a vent port in the body and communicating with the flow chamber at its upper end, valving means within the flow chamber to control the iiow of iiuidthrough the outlet and vent ports communicating therewith and having a longitudinally shiftable valve stem projecting upwardly and into the trap chamber to terminate therein, over center cam operated actuating means carried by the body at the upper end thereof and including a vertically shiftable actuating stem depending into the trap chamber to engage the valve stem, and sealing means between the actuating stem and the body, said actuating means including a cap secured to and closing the upper end of the body and having an upwardly projecting tubular post slidably receiving the actuating stem, a cam plate rotatably carried by the post and engaging the upper end of the actuating stem and having a laterally projecting actuator arm projecting therefrom, and a spring in the trap chamber and engaging the actuating stem upwardly and into engagement with the cam plate, said valving means including an annular seat ring fixed in the iiow chamber between the inlet and vent ports, a valve element in the flow chamber below the seat ring and yieldingly coupled with the lower end of the valve stem, and a compression spring in the flow chamber below the valve member and yieldingly urging the said chamber upwardly into engagement with the seat ring, said sealing means including a bellows sleeve engaged in the trap chamber and having a iiange at its upper end secured to and sealed with the body and a ilange at its lower end secured to and sealed with the actuating stem.

8. A vent valve of the character referred to including an elongate vertically disposed tubular body having a partition therein and defining an upper trap chamber and a lower elongate flow chamber, an inlet port in the body and communicating with the tlow chamber at a point intermediate its ends, an outlet port in the body and communicating with the ilow chamber below the inlet port and a vent port in the body and communicating with the liow chamber above the inlet port, an annular valve seat about the outlet port, an annular valve seat ring in the iiow passage between the inlet and vent ports, a vertically shiftable valve member in the ow chamber and adapted to be shifted into and out of engagement with the seat and seat ring to selectively control the flow of liuid out through the outlet and vent ports, a spring in the flow chamber normally yieldingly urging the valve element upwardly therein, a vertically shiftable valve stem extending from the iiow chamber through the partition and into the trap chamber, means yieldingly coupling the valve stem with the valve member, over center cam actuating means at the upper end of the body and including a vertically shiftable actuating stem depending into the trap chamber, means coupling the actuating stem with the valve stem, and bellows type sealing means in the trap chamber and sealing between the actuating stem and the body.

9. A vent valve of the character referred to including, an elongate vertically disposed tubular body having a partition therein and defining an upper trap chamber and a lower elongate ow chamber, an inlet port in the body and communicating with the iiow chamber intermediate the ends, an outlet port in the body communicating with the flow chamber below the inlet port and a vent port in the body and communicating with the tlow chamber above the inlet port, an annular valve seat about the outlet port, an annular valve seat ring in the flow passage between the inlet and vent ports, a vertically shiftable valve member in the ow chamber and adapted to be shifted into and out of engagement with the seat and seat ring to selectively control the flow of fluid out through the outlet and vent ports, a spring in the flow chamber normally yieldingly urging the valve element upwardly therein, a vertically shiftable valve stem extending from the ow chamber through the partition and into the trap,V chamber, means yieldingly couplingV the valve stem withl the valve member, .over center cam. operatedl actuating meansatvtlie upper end of therbody and includingfla vertically shiftbl actuating stem' dependingl into the trap chamber,- means couplingrxthe.ac1natingsiem With the valvestem, andbellws typefsealing/meansin fac'e Aare atY different. angles with respect Lto Y the lngituvalve member rwhen -the member isseated 'one-the. ring.

10. Avente valvef as .set forth1inic1aim'w9"wherein-said l Y Y 12@ annulanvalve seat about the outlet -port and valve member have oppsed upwardly-andbtvdly inclined faces,

diverge'. radially otwardrly*V from each" other-When the outer periphery of d*the inclined "facetheren and carry;`

in'gla sealing ringwhich projeets `lofr'igitlidinall'y therefrom" and .l enggesA sad opposedA falce?y on" the" vl've member when the m'emb'erissreated." Y Y v References Ciiin the,leef-thislpafem-f UNITED STATES- PATENTS Bueknam Jan;'19,'1943 Y 2,484,628? Levalley w e; v f 1 r ocr.` 11, 1949 2,682,386'l Lindsay Y A Junel 29,A 1954 2;703,f106 BQrgerd 1. .Marg-l 1, 11955 u un; 

